This activity uses an interactive abacus to help develop and reinforce pupils' understanding of place value. The abacus has three pegs onto which beads are dropped, representing units, tens, and hundr...More: lessons, discussions, ratings, reviews,...

Choose integers or numbers with decimal places, then try to make up the target number by choosing numbers from the units, tens, hundreds, depending on your original choice. Available in Arabic, Bengal...More: lessons, discussions, ratings, reviews,...

First level in a collection of five Number Grid activities. It displays a section of a matrix containing a set of consecutive whole numbers. A move from one number to the next within a row is a change...More: lessons, discussions, ratings, reviews,...

Second level in a collection of five Number Grid activities. It displays a section of a matrix containing a set of consecutive whole numbers. A move from one number to the next within a row is a chang...More: lessons, discussions, ratings, reviews,...

Third level in a collection of five Number Grid activities. It displays a section of a matrix containing a set of consecutive whole numbers. A move from one number to the next within a row is a change...More: lessons, discussions, ratings, reviews,...

Fourth level in a collection of five Number Grid activities. It displays a section of a matrix containing a set of consecutive whole numbers. A move from one number to the next within a row is a chang...More: lessons, discussions, ratings, reviews,...

Fifth level in a collection of five Number Grid activities. It displays a section of a matrix containing a set of consecutive whole numbers. A move from one number to the next within a row is a change...More: lessons, discussions, ratings, reviews,...

The Abacus Java Applet/Application is an implementation of an Abacus counting machine. The machine displays a total for the number represented by the machine's current state in addition to each digits...More: lessons, discussions, ratings, reviews,...

An interactive Java gadget simulating soroban--the Japanese abacus. Options inlude selecting the number system base and the number of wires. The applet displays the number matching the configur...More: lessons, discussions, ratings, reviews,...

An interactive Java gadget simulating suan pan--the Chinese abacus. Options include selecting the number system base and the number of wires. The applet displays the number matching the configu...More: lessons, discussions, ratings, reviews,...

An interactive Java applet showing one or two Russian abacuses with options to select the base of the number system and the number of wires. The applet displays the number matching the current config...More: lessons, discussions, ratings, reviews,...

Use this tool to reinforce students' understanding of place value. Students choose values from groups of units, tens, and hundreds, or decimal values, to reach the target number. Versions of this acti...More: lessons, discussions, ratings, reviews,...

This module can be used as a starting point for learning multiplication and division by 10, 100 and 1000 using place value of digits and also by moving the decimal point. It includes converting betwee...More: lessons, discussions, ratings, reviews,...

Number Pieces Basic helps students develop a deeper understanding of place value while building their computation skills with multi-digit numbers. Students can use the number pieces to represent multi...More: lessons, discussions, ratings, reviews,...

This material is based upon work supported by the
National Science Foundation under Grant DUE-0226284.
Any opinions, findings, and conclusions or recommendations
expressed in this material are those of the author(s)
and do not necessarily reflect the views of the
National Science Foundation.